Advanced manufacturing techniques have obtained global interest, especially fabricating nanotechnology products. One such technique called atomic layer deposition (ALD) has without doubt manifested itself as an attractive key-enabling nanotechnology that is able to deposit ultrathin, uniform, conformal and pinhole-free nano-films on complex topography. It is utilized in fabrication of superconductors, solar cells, fuel cells, microelectronics, and medical equipment, among other applications. Nonetheless, the ALD process properties and thermal, chemical and flow behaviors are still not well enough understood to provide detailed information, resulting in numerous impasses. In this study, a novel slotted inlet manifold is designed and analyzed in comparison to that of the standard spliced eight-inlet manifold that is currently adopted in a Gemstar 6 reactor. By means of computational fluid dynamics (CFD) the study is centered in observing the impact on the deposition rate due to the different flow patterns of the two ALD reactor designs. The film material of interest is Al 2 O 3 fabricated by the sequential injection of TMA and O 3 precursors with argon gas as the purge substance in the ALD reactors. The numerical model adopts the governing laws of the conservation of mass, momentum, energy, species, and kinetic chemical reactions to analyze the behavior in a reactor scale domain. These equations are solved by using the software ANSYS Fluent and ChemkinPro. The end results are validated by available literature.

Bending curved metal plate is an important process for many heavy industries such as shipbuilding. It is a basic process to manufacture hull surface. The conventional method is the so-called line heating method, which is not only labor intensive but also inefficient and error-prone. We have presented a new method of incremental bending. In this paper the incremental bending system is explained from its hardware and software. A kind of curved metal plate is formed by experiment and finite element simulation. The manufactured workpiece is of high quality with smooth surface. The presented method can be successfully used to form curved metal plate. It is a highly flexible forming method. It would have a wide application in industry.

Associated with manufacturing and assembly processes, inevitable geometric deviations have a decisive influence on the function and quality of products. Therefore, their consideration and management are important tasks in product development. Moreover, to meet the demand for short development times, the front-loading of design processes is indispensable. This requires early tolerance analyses evaluating the effect of deviations in a design stage, where the product’s geometry has not yet been finally defined. Since such an early tolerance consideration allows quick and economic design changes seeking for robust designs, it is advisable that the design engineer, who is entirely familiar with the design, should take this step. For this purpose, this paper presents an easy-to-use CAD-based tolerance analysis method for skeleton models. The relevant part deviations are represented by varying geometric dimensions with externally driven family tables. The approach comprises the strength of vector-based methods but does not require an expensive set-up of tolerance analysis models. Particularly, the novelty of this method lies in the CAD-internal sampling-based tolerance analysis of simple geometries without the use of expensive CAT software. This enables designers to evaluate the effect of tolerances already at the preliminary design stage. Using a case study, the presented approach is compared with the conventional vector-based tolerance analysis.

This paper studies the use of an engineering equation solver (EES) software to improve the students’ perceptive of the Air conditioning and Nozzle analysis in courses such as heat transfer and applied gas dynamics. EES lets students to concentrate on design engineering applications. Also the students will have the skill to see instant results to differences of the design circumstances as well as diverse parameters that would touch diverse categories of engineering projects. The proposed tool also gives students the ability to determine thermodynamics properties of any fluid, solve different mathematical equations with many variables and perform optimization and analysis. In this paper, condenser of air conditioning as a heat transfer project was used as an example to demonstrate EES to the students. The student’s feedback shows that the use of the proposed tool significantly improves the student learning experience in thermodynamics and heat transfer courses and other mechanical engineering courses such as thermal design analysis, make the course more dynamic, and motivate the students to learn the material fast and effectively.

This paper presents a method for teleoperation using virtual reality (VR) headsets and glove-like interfaces, and evaluates the proposed system with a preliminary user study. For effective teleoperation, it is imperative that the operator possess adequate feedback regarding the remote device state. This work utilizes commodity VR technology to replicate critical remote task features in a purely software/virtual environment from sensor data. The 3D visual feedback is immersive yet simplified to reduce sensory burden — only relevant features are reflected. The system is designed and executed on a real robotic platform, and preliminary operation is encouraging. Moreover, high dexterity VR gloves provide an intuitive and natural interaction for the operator, as the user may present fluid and motion commands without the use of an unnatural game-controller. A user study was conducted to compare performance along several relevant metrics between use of glove-like and game controller interfaces for VR teleoperation. These metrics include time to completion, path length, and jerk as a measure of path smoothness. The results of said study suggest strongly that teleoperator performance improves with the adoption of glove-like interfaces.

The increasing complexity of engineering and technology requires that students master an increasing amount of abstract knowledge to remain competitive in today’s job market. However, today’s students find it difficult to create mental images of abstract concepts, due to lack of real world experience. This problem is more evident in advanced design classes teaching product design concepts and methodologies. In this paper, we introduce a system engineering software package that is used in our capstone design class, with which students are able to create their own framework of product development activities, control information flows, and manage tools and engineering models in each activity. This allows them to plan out and manage their projects using the design methodologies that they learned in class. We assessed student learning in the capstone design class for the last 7 semesters. Independent Samples t-Test and factorial ANOVA are used to analyze the student performance before and after using the software package. We have observed that in the design classes, the system engineering software enables students to practice design methodologies by visualizing and managing product development processes. This helps students not only understand the abstract design methodologies, but also apply the methodologies to their projects and accomplish them more efficiently.

A non-linear regression model using SAS/STAT (JMP ® software; Proc regression module) is developed for estimating the elastic stiffness of finite composite domains considering the combined effects of volume fractions, shapes, orientations, inclusion locations, and number of multiple inclusions. These estimates are compared to numerical solutions that utilized another developed homogenization methodology by the authors (dubbed the generalized stiffness formulation, GSF) to numerically determine the elastic stiffness tensor of a composite domain having multiple inclusions with various combinations of geometric attributes. For each inclusion, these considered variables represent the inclusions’ combined attributes of volume fraction, aspect ratio, orientation, number of inclusions, and their locations. The GSF methodology’s solutions were compared against literature-reported solutions of simple cases according to such well-known techniques as Mori-Tanaka and generalized self-consistent type methods. In these test cases, the effect of only one variable was considered at a time: volume fraction, aspect ratio, or orientation (omitting the number and locations of inclusions). For experimental corroboration of the numerical solutions, testing (uniaxial compression) was performed on test cases of 3D printed test cubes. The regression equation returns estimates of the composite’s ratio of normalized longitudinal modulus (E11) to that of the matrix modulus (Em) or E11/Em when considering any combination of all of the aforementioned inclusions’ variables. All parameters were statistically analyzed with the parameters retained are only those deemed statistically significant (p-values less than 0.05). Values returned by the regression stiffness formulation solutions were compared against values returned by the GSF formulation numerical and against the experimentally found stiffness values. Results show good agreement between the regression model estimates as compared with both numerical and experimental results.

The purpose of this paper is to develop Graphical User Interfaces (GUI) in MATLAB’s 1 Finite Element educational program and describe how MATLAB GUI programs have been used as educational tools to train Engineering Technology students and improve the success of the students in the Finite Element course. The complexity of FE analysis forces most of the course to focus on the theoretical aspects of generating FEA models, rather than the application of this analysis tool to solve real world problems. New tools are needed to improve the teaching of Finite Element due to the complexity of FE analysis. FEA can be performed by many commercial difficult FEA software with very specific data entry requirements available in the market. Engineering Technology students improve their learning when the coursework is less theoretical, and more application. Hence, a graphical user interface (GUI) application can provide an additional tool to help teach Engineering technology students. The Finite Element Educational Program has been developed to make the course more challenging to increase the interest in the finite element course of the students and overcome the difficulties of complex software. I have developed a Finite Element Educational Program using a MATLAB GUI for spring, bar, truss and beam elements to improve student learning of difficult engineering concepts, along with gaining essential knowledge of finite element analysis and design content knowledge. For example, the total stiffness matrix and reduced matrix for the given problem are calculated in the designed program, and these calculated values are not available in any commercial FEA software because these programs are not aimed at education. For over five years, The Finite Element Educational Program results show improvement in student knowledge of difficult engineering concepts and has made finite element lessons easier for students to learn and understand.

In the steelmaking process, reheating furnaces are used to reheat steel slabs to a target rolling temperature. The bottom intermediate zone inside the reheating furnace plays a decisive role in controlling the slab temperature distribution before slabs enter the soaking zone. Efforts to maintain a uniform slab surface temperature and thus enhance product quality require a good understanding of the furnace’s operation. However, traditional physical experiments are costly and have high risks as well. In this study, a three-dimensional steady-state computational fluid dynamics (CFD) model was developed to investigate the flow field in the bottom intermediate zone of a full-scale reheating furnace. The commercial software ANSYS Fluent ® was used to solve the transport equations to predict the flame length, heat transfer, and gas temperature near the slab. Total input mass flow rate, preheated air temperature, and air/fuel ratio were selected to investigate the comprehensive influence of the furnace’s performance, which can be evaluated from the flame length, flame angle, and average gas temperature near the slab. Importantly, an orthogonal experimental design was conducted to optimize the evaluation factors by considering the multi influencing factors simultaneously. The simulation results indicate that a higher mass flow rate produces a lower upwards flame angle, which can prevent the hot spot detected on the slab surface. A higher preheated air temperature leads to a higher average gas temperature in this furnace; meanwhile, the flame becomes shorter by enhancing the air-fuel ratio.

In underground coal mines, miners face the hazard of being struck or pinned by a piece of mobile mining machinery. Proximity detection systems have been developed and are used by the industry to protect miners around these machines by detecting the presence of the miners and automatically issuing warnings or disabling machine motion when a miner is in potentially dangerous proximity. These systems were originally developed for continuous mining machines, slow-moving machines that move on bulldozer-style tracks, and are now mandated by the Mine Safety and Health Administration (MSHA) to be used on continuous mining machines. These systems are now being adapted to other underground vehicles, such as shuttle cars, scoops, and battery haulers — vehicles that move on rubber tires at much higher speeds. There are concerns that the detection range of these systems may not provide for an adequate stopping distance on these faster moving machines. To address these concerns, researchers have developed a dynamic modeling system to determine the stopping distance of mobile underground coal equipment. This model can be used in conjunction with worker escapability data and/or information on interaction with other vehicles to provide insight into whether or not proximity detection systems will be adequate for the underground mining workplace. This paper details the background, development, and operation of the resulting application software, focusing on the utility of the graphical user interface to visualize the generated data. The refined data developed by this process can then be utilized by mine operators and proximity detection system manufacturers to more accurately determine the detection range needed to provide effective protection for miners working in an underground mining environment.

In order to eliminate occurrences of flutter of low pressure turbine blades it is necessary to understand the associated unsteady aerodynamics. For this reason, an experimental and numerical study of controlled flutter (travelling wave mode) in a linear turbine blade cascade oscillating in a torsional as well as translation motion is conducted. Unsteady aerodynamic forces and moments were measured on a subsonic eight-blade turbine cascade rig where central four blades are flexibly mounted each with two degrees of freedom. Thin blades in the cascade represent the tip section of the last stage rotor blades, which defines the turbine overall performance. A commercially available 3D CFD software ANSYS CFX is used to simulate the unsteady aerodynamic loading in the blade cascade. Experimental data and simulations are compared and influence of aerodynamic forces and moments on flutter is analysed.

This paper presents the development of a service robot platform for various assistive tasks in human-centered environment. The main design objective is to enable the robot to safely navigate indoor areas and to provide cross-platform accessibility to human-users. To accomplish the goal, two technical design requirements which include the rough-terrain locomotive mechanism and the web-server based operating system are addressed and explored in this study. First, the overall control system architecture of the robot which consists of three different layers (human-interaction, environment-interaction and movement) is presented. Then, the mechanical and electronic specification of the robot’s dual drive system and the power management system are described with their design process. The robot’s software platform (which consists of the server, client and real time controller) is also provided for the selected service task. Last, the built platform is tested and evaluated through experimentations in the real world settings.

Boiler systems have many factors that affect the efficiency of the air conditioning process. A traditional control system is complicated and requires physical hardware and software programming. The modern operator console is more compact and works better. Regardless of the boiler system, the operator can run it automatically, allowing changes in many variables such as fuel input, air combustion, water feed flow, steam temperature, etc. In fact, it is impossible to control all of these variables simultaneously in the manual mode. Modern systems have been developed to a high degree of precision that can provide excellent results in maintaining high levels of efficiency, reliability, and safety. The Programmable Logic Controller (PLC) was developed in 1968, and since then it has improved rapidly and applied to many manufacturing industries. Besides the Allen Bradley PLC, other modules were developed such as Human Machine Interface (HMI), Variable Frequency Drives (VFDs), and safety components. In this paper, the Allen Bradley PLC ControlLogix family 1756 model is used to control the boiler system. In addition, this work focuses on improving the boiler efficiency by comparing between the manual and automatic control the fuel-air ratio.

A nonlinear dynamics investigation is conducted on the frequency-amplitude response of electrostatically actuated micro-electro-mechanical system (MEMS) clamped plate resonators. The Alternating Current (AC) voltage is operating in the realm of superharmonic resonance of second order. This is given by an AC frequency near one-fourth of the natural frequency of the resonator. The magnitude of the AC voltage is large enough to be considered as hard excitation. The external forces acting on the MEMS resonator are viscous air damping and electrostatic force. Two proven mathematical models are utilized to obtain a predicted frequency-amplitude response for the MEMS resonator. Method of Multiple Scales (MMS) allows the transformation of a partial differential equation of motion into zero-order and first-order problems. Hence, MMS can be directly applied to obtain the frequency-amplitude response. Reduced Order Model (ROM), based on the Galerkin procedure, uses mode shapes of vibration for undamped circular plate resonator as a basis of functions. ROM is numerically integrated using MATLAB software package to obtain time responses. Also, ROM is used to conduct a continuation and bifurcation analysis utilizing AUTO 07P software package in order to obtain the frequency-amplitude response. The time responses show the movement of the center of the MEMS circular plate as a function of time. The frequency-amplitude response allows one to observe bifurcation and pull-in instabilities within the nonlinear system over a range of frequencies. The influences of parameters (i.e. damping and voltage) are also included in this investigation.

The aerodynamic analysis of vehicles using Computational Fluid Dynamics (CFD) is a powerful tool that is used to explore and investigate how air flow behaves around the vehicle, gives a qualitative idea of aerodynamic behavior and provides engineers with the information necessary to design the pieces that will be tested in the wind tunnel. This technique allows to find the values of forces and moments to get an idea of the drag resistance and lift forces on the vehicle. It is also possible to determine the position of the center of pressure that exerts a vital importance in the definition of the directional stability of the vehicle in its lateral dynamics. On the other hand, it offers the advantage of being able to see many variables of the problem that are very difficult to access in reality, for example to see current lines, vortex shedding, fields of pressures around the vehicle. Although the use of CFD has become a common practice in the automotive industry in recent decades, it is still not considered as a single technique, since one of the limitations is related to the dynamics of a turbulent flow is quite complex so which analytical and computational study depends on what is called Turbulence Models. This article aims to show the aerodynamic design process by CFD simulation of a Baja SAE vehicle chassis using Ansys software, widely used for simulation of static charges, thermodynamics, fluid mechanics, multiphysics systems and vibrations and to provide information that can be validated experimentally in the future.

Norway conducts operations on a variety of structures in the North Sea; e.g. oilrigs, monopole windmills, subsea trees. These structures often require subsea installation, observation, and maintenance. Research and technology that can improve the efficiency of these operations are of high interest to the nation. A remotely operated vehicle (ROV) can assist in these operations. However, the ROV pilot must observe and adjust the vehicle and its motion in accordance with its task, but modified due to impending forces. Automation of this motion is the desired goal. This paper researches the motion of an ROV induced by the motion of the robotic manipulators, motor torques, and fluid buoyancy. The research introduces a new method in engineering dynamics: the Moving Frame Method (MFM). Lie Group Theory and Cartan’s notion of moving frames are the foundation of the MFM. This research extends previous work in significant ways. This research accounts for the motor torques, fluid viscosity and the mass of the manipulator’s arms. Interactive visualization on hand-held devices is also an integral part of this research. The Web Graphics Library (WebGL) is a JavaScript API for rendering interactive 3D and 2D graphics within any compatible web browser without the use of plug-ins. This work visualizes the results, interactively, on 3D web pages, viewable on cell phones using WebGL. This work invites further research into improved numerical methods, solid/fluid interaction and the design of Autonomous Underwater Vehicles (AUV). AUVs beckon an era of Artificial Intelligence when machines think, communicate and learn. Rapidly deployable software implementations will be essential to this task. This paper demonstrates the MFM clears the path toward such technological innovations.

Remotely operated vehicles, ROV, are highly versatile robotic systems, which are currently the best alternative to carry out deep-sea tasks, that otherwise could compromise the safety of human lives. These vehicles are commonly used by several industries such as offshore oil companies, offshore wind energy companies and environmental organizations. These underwater vehicles may be classified as Free-Swimming Systems, FSS, or Tether Management Systems, TMS. Tether Management Systems use the cable to transmit data and steering commands, and as a mean for power supply. It is known that the cable has a strong influence on the dynamics and maneuverability of a ROV. To improve the motion accuracy and stability of the control of a ROV, it is necessary to understand the nature and to estimate the value of the mutual reaction forces between the ROV and the cable. This research seeks the modeling of the overall underwater tethered vehicle, by iteratively coupling the results from the finite element analysis, FEA, of the cable with the dynamic model of the ROV, as obtained by using the standard Newton-Euler formulation. Morison equation is employed to obtain the cable transient response. In this work, the ROV tether is defined as a flexible, slender cylinder, with circular cross section and made of a material with nonlinear elastic behavior. The cable is assumed to be in a specific extended initial configuration, with one of its ends fixed in ground. The FEA analysis of the cable is performed with the help of the commercial software COMSOL Multiphysics. A commercial small ROV is selected as the case study to apply the Newton-Euler method, considering the location of its actuators and other actual parameters such as mass, matrix of mass moments of inertia and drag coefficients. To include the cable forces into the dynamic model of the ROV, it is necessary to perform an iterative process between the cable analysis results and the ROV open loop response. The modeling approach starts with an FSS system initial velocity, which is fed into the cable FEA analysis. Both analyses are iterated, following a mutual feedback scheme, until results converge, obtaining the complete tethered vehicle model. The main achievement of this investigation is to observe the cable influence on the ROV, providing results that prove to be extremely useful for future work on the control system design, taking into account the disturbances introduced by the cable.

This paper presents the development of a lower body for a full-size humanoid platform, HART (Human Assistive RoboT). The design objective of HART is to enable the robot to drive off-the-shelf vehicles in human-centered environments. To accomplish the goal, two technical design requirements which include kinematic adaptation and low-cost manufacturing are addressed and explored in this study. First, the overall hardware configuration and software control architecture of HART are presented. Then, the kinematic and dynamic specification of each joint and its design process are described. The kinematic analysis and motion planning of HART are also provided for the vehicle handling task such as control input manipulation. Last, the built platform is tested and evaluated through experimentations using two different types of ground vehicles.

Contact angle measurements are important to determine surface and interfacial tension between solids and fluids. A ‘water-wet’ condition on the rock face is necessary in order to extract oil. In this research, the objectives are to determine the wettability (water-wet or oil-wet), analyze how different brine concentrations will affect the wettability, and study the effect of the temperature on the dynamic contact angle measurements. This will be carried out by using the Cahn Dynamic Contact Angle. Analyzer DCA 315 to measure the contact angle between different fluids such as surfactant, alkaline, and mineral oil. This instrument is also used to measure the surface properties such as surface tension, contact angle, and interfacial tension of solid and liquid samples by using the Wilhelmy technique. The work used different surfactant and oil mixed with different alkaline concentrations. Varying alkaline concentrations from 20ml to 1ml were used, whilst keeping the surfactant concentration constant at 50ml.. It was observed that contact angle measurements and surface tension increase with increased alkaline concentrations. Therefore, we can deduce that they are directly proportional. We noticed that changing certain values on the software affected our results. It was found that after calculating the density and inputting it into the CAHN software, more accurate readings for the surface tension were obtained. We anticipate that the surfactant and alkaline can change the surface tension of the solid surface. In our research, surfactant is desirable as it maintains a high surface tension even when alkaline percentage is increased.

Background: Pressure distribution for transtibial amputees (TTA) patients varies at the limb socket interface according to several factors. Although socket technology is getting more advanced, the majority of researchers are still facing problems with relief areas. Objectives: This study focused on the theoretical and experimental aspects of the design to figure out patients’ sensitivity to pain when wearing sockets. Relief areas were analyzed using data collected from patients’ centers and optimized under different static and dynamic conditions. Methods: Finite element trials and DOE optimization using Design Expert 8 software and analysis of variance (ANOVA) revealed that holes with relief areas are appropriates for lower extremities patients where scanning electron images (SEM) of the worn areas show direct relations between relieved sockets with holes at fibula head (FH) and patient lifestyle and activity. Clinical Relevance: A patient that moves rather slowly, as a result of old age or sedentary level of activity would greatly benefit from the FH socket hole implementation, and thus reduces the wear of socket materials after longer period of time and increases the level of comfort of patient skins. the interviews conducted were evident that patients endured pain at the PT and FH. Moreover, further studies were performed on the FH, and results revealed that lateral forces play a major role and is influenced by the lifestyle of the patient.